WO2017159468A1

WO2017159468A1 - Operation lever

Info

Publication number: WO2017159468A1
Application number: PCT/JP2017/009085
Authority: WO
Inventors: 雅士渥美
Original assignee: 株式会社タダノ
Priority date: 2016-03-14
Filing date: 2017-03-07
Publication date: 2017-09-21
Also published as: CN108473288A; CN108473288B; JP6342933B2; JP2017165512A; KR20180097601A; KR102061161B1

Abstract

[Problem] To provide an inexpensive operation lever having an overstroke function and a structure that is simple and easy to maintain. [Solution] An operation lever 31 includes: a fork 32 that is rotatable about a rotation shaft 33; a handle 41 that is provided to the fork 32 and rotates the fork 32 about the rotation shaft 33; a slide plate 63 to which a spool 36 of a hydraulic control valve 35 is connected and which is supported by the fork 32 in a state in which the slide plate 63 is reciprocable along a slide direction orthogonal to an axis of the rotation shaft 33 with respect to a predetermined neutral position; a cover 62 that guides the reciprocation of the slide plate 63; and a coil spring 64 that is arranged between the fork 32 and the cover 62 and that is engaged with the slide plate 63 so as to urge the slide plate 63 to return to the neutral position when the slide plate 63 slides from the neutral position.

Description

Operation lever

The present invention relates to an operation lever for a vehicle-mounted crane or other work device, and particularly to an operation lever having an overstroke function.

Conventionally, cranes mounted on vehicles are hydraulically driven. Operations such as boom expansion and contraction are performed by switching the hydraulic control valve. Therefore, the vehicle-mounted crane includes an operation lever for the operator to operate the hydraulic control valve. Some of these operation levers have an overstroke function (for example, Patent Document 1). An operation lever having an overstroke function has two modes of a normal stroke and an overstroke.

The normal stroke mode corresponds to the operation of the operation lever from the state where the spool of the hydraulic switching valve is in the neutral position until it reaches the stroke end. The overstroke mode corresponds to the operation of the operation lever when the operation lever is further moved from the state where the spool has reached the stroke end. In the normal stroke mode, switching of the operation direction such as boom expansion / contraction and undulation and change of the operation speed are performed by operating the operation lever. On the other hand, in the overstroke mode, only the operation speed is changed by operating the operation lever.

FIG. 13 is a view showing an operation lever 101 having a conventional overstroke function.

The operation lever 101 includes a lever base 103 (also referred to as “fork”), a handle 112, and a mode switching mechanism 115, and the overstroke function described above is exhibited through the mode switching mechanism 115. . The lever base 103 is supported by a rotation shaft 113 and rotates about the rotation shaft 113 when the handle 112 is operated in the directions of

arrows

116 and 117. That is, when the handle 112 is operated in the directions of

arrows

116 and 117, the spool 102 of the hydraulic control valve is slid in the directions of

arrows

118 and 119, respectively. The sliding direction of the spool 102 determines the operating direction of the hydraulic actuator that performs expansion / contraction / undulation of the boom. The slide amount of the spool 102 is adjusted by operating the handle 112, and the operating speed of the hydraulic actuator is determined by the slide amount.

When the handle 112 is operated in the normal stroke mode, the spool 102 slides as described above. When the handle 102 is further operated in the same direction when the spool 102 reaches the stalk end, the operation lever 101 is overstroked (in this case, the mode is switched to the overstroke mode), and the spool 102 is maintained in the stroke end state. Only the lever base 103 is rotated as it is. The amount of rotation of the lever base 103 in this mode corresponds to the opening of the engine throttle via a predetermined link mechanism. That is, the discharge amount of the hydraulic pump is adjusted, and the operating speed of the hydraulic actuator is adjusted.

As described above, the operation lever having the overstroke function can control the operation speed over a wide range without controlling the operation direction of the boom by a single operation of the operation lever.

Japanese Utility Model Publication No. 3-025210

As shown in FIG. 13, the mode switching mechanism 115 includes a shaft 104 coupled to the spool 102, a cylindrical case 110 to which a handle 112 is attached, a spring 106 and

spring seats

107 and 108, a collar 109, and a cylindrical case 110. A bolt 111 that fastens the shaft 104 together with the spring seat 108 and the handle 112, and a lid 105 that closes the end of the cylindrical case 110. One end of the shaft 104 is connected to the spool 102 of the hydraulic control valve, and the other end is in contact with the spring seat 107. The elastic force of the spring 106 is applied to the shaft 104 via the

spring seats

107 and 108, and the shaft 104 is always urged so as to protrude outward (to the left in the figure) from the cylindrical case 110. .

FIGS. 14 and 15 are enlarged views of the operation lever 101, showing the operation in the overstroke mode.

When the handle 112 is operated in the direction of the arrow 117 and the spool 102 reaches the stroke end (see FIG. 14A), and the handle 112 is further operated in the same direction (overstroke), the same operation is performed. As shown in the figure (B), the spring 106 is bent by being pushed by the shaft 104, and the shaft 104 slides toward the handle 112 side. Thereby, the lever base 103 is rotated from the position shown in FIG. 14A to the position shown in FIG. 14B without moving the spool 102. The same applies to the case where the handle 112 is operated in the direction of the arrow 116, and the spool 102 is shown in FIG. 15 (B) from the position shown in FIG. 15 (A) without being moved while reaching the stroke end. The lever base 103 is rotated to the position.

By the way, among the components constituting the operation lever 101, the

spring seats

107 and 108 and the cylindrical case 110 are manufactured by drawing, and the shaft 104 and the collar 109 are manufactured by lathe processing. Therefore, the processing cost of these parts increases, and the number of parts increases, so that the number of assembly steps increases. That is, not only the manufacturing cost of the operation lever 101 increases, but also maintenance is not easy.

The present invention has been made based on such a background, and an object thereof is to provide an inexpensive operation lever having an overstroke function with a simple and easy-to-maintain structure.

(1) An operation lever according to the present invention includes a base that can be rotated about a predetermined rotation axis, a handle that is provided on the base, and that rotates the base about the rotation axis. A slide plate supported by the base in a state where the operation target is connected and can be reciprocated along a slide direction orthogonal to the rotation axis with respect to a predetermined neutral position, and the slide plate reciprocates. A guide plate that guides the movement, and is disposed between the base and the guide plate and is engaged with the slide plate so that the slide plate returns to the neutral position when it slides from the neutral position. And an elastic member for urging the slide plate.

According to this configuration, the slide plate is supported with respect to the base, and the slide plate is slidable in the sliding direction while being supported by the guide plate. And since the elastic member is arranged between the base and the guide plate, when the slide plate is displaced from the neutral position against the elastic force of the elastic member in the neutral position, The elastic member elastically urges the slide plate to return to the neutral position.

Now, when the handle is operated, the base receives a torque around the rotation axis. Since an operation target (typically, a spool of a hydraulic control valve) is connected to the slide plate, an external force corresponding to the torque acts on the slide plate from the operation target. When the magnitude of the external force is smaller than the elastic force exerted by the elastic member at the neutral position, only the spool is slid without displacing the slide plate from the neutral position. That is, in this case, the operation mode of the operation lever corresponds to the normal stroke mode. Further, when the magnitude of the external force is larger than the elastic force exerted by the elastic member in the neutral position (typically, the handle has a larger force when the spool as the operation target has reached the stroke end. ), The slide plate is displaced, and the base is further rotated relatively. When the operating force to the handle is reduced, the spool remains in the stroke end state, and the slide plate returns to the neutral position by the elastic force of the elastic member. That is, in this case, the operation mode of the operation lever corresponds to the overstroke mode.

Thus, a structure in which the operation lever exhibits an overstroke function is realized by only a part of the base, the slide plate, the guide plate, and the elastic member. Moreover, the elastic member does not require a special structure, and the slide plate and the guide plate are the same. Therefore, the manufacture of these parts does not require the conventional drawing, lathe and other machining, and the number of parts of the operation lever is reduced as compared with the prior art.

(2) A pair of seat surfaces facing the slide direction are formed on the base and the guide plate, and the elastic member is held on the pair of seat surfaces in a state where the slide plate is in the neutral position. May be. The slide plate has a pair of engaging portions facing each other along the sliding direction, and one engaging portion is formed on the seat surface of the guide plate when the slide plate slides to one side in the sliding direction. Instead, it is formed to engage with the elastic member and sandwich the elastic member with the seat surface of the base, and the other engaging portion is when the slide plate slides to the other side in the sliding direction. It is preferable that the elastic member is engaged with the elastic member instead of the seat surface of the base and is sandwiched between the elastic member and the sheet surface of the guide plate.

According to this configuration, when the slide plate is in the neutral position, the elastic member is held between the seat surface of the base and the seat surface of the guide plate. Since these seat surfaces are constituted by a part of the base and the guide plate, no special parts are required to hold the elastic member. In the above-described overstroke mode, the slide plate is slid. At this time, the elastic member is engaged between the seat surface of the base and the other engagement portion of the slide plate or one of the slide plates. It is sandwiched between the joint portion and the sheet surface of the guide plate, exerts the elastic force, and tries to return the slide plate to the neutral position.

(3) The seat surface of the base is composed of a wall portion orthogonal to the sliding direction, and the wall portion has a through hole to which the slide plate is slidably fitted and the insertion of the elastic member is restricted. It is preferable. The guide plate has a pair of side portions, and is formed of a mountain-shaped member erected between the base and the handle, and the sheet surface of the guide plate is disposed opposite to the wall portion. It is preferable that the one side portion includes a through hole that is slidably fitted to the slide plate and restricts insertion of the elastic member.

In this configuration, the seat surface of the base is constituted by a wall portion of the base, the guide plate is constituted by a chevron member used as a general-purpose product, and the seat surface of the guide plate is formed by the chevron. It consists of one side of the member. That is, the guide plate is also composed of a simple member. In addition, through holes are formed in the pair of sheet surfaces, the slide plate is slidably held in the slide direction. That is, the slide plate is supported with a simple structure.

(4) An opening penetrating in the direction along the rotational axis is provided at the center of the slide plate, and the pair of engaging portions are formed at portions facing the slide direction on the inner peripheral surface of the opening. It is preferable. The elastic member is preferably disposed in the opening.

In this configuration, the elastic member interposed between the base and the guide plate is disposed in the slide plate, and the base, slide plate, guide plate, and elastic member are laid out in a compact layout. Is done. In addition, this layout can be realized very simply by arranging the elastic member in the opening provided in the slide plate.

(5) The elastic member is preferably a coil spring having a predetermined inner diameter. It is preferable that the slide member is a flat bar, the opening has a rectangular shape, and the pair of engaging portions are projecting pieces inserted into the coil spring.

In this configuration, general-purpose products can be used as the material for both the elastic member and the slide plate. Moreover, since the coil spring as the elastic member is supported by a pair of projecting pieces provided on the slide plate, the coil spring is easily and reliably held at the neutral position, and the slide plate slides. Even if it exists, the said coil spring can be elastically deformed stably.

According to the present invention, the number of parts of the operation lever is reduced, and each part can be manufactured without using drawing or lathe processing. Therefore, an inexpensive operation lever having an overstroke function with a simple and easy-to-maintain structure can be provided.

FIG. 1 is a side view of a vehicle-mounted crane 10 including an operation lever device 30 according to the present embodiment. FIG. 2 is a rear view of the vehicle-mounted crane 10 including the operation lever device 30. FIG. 3 is a front view showing the operation lever device 30. FIG. 4 is a perspective view showing the operation lever in a stacked state in the operation lever device 30. FIG. 5 is a plan view for explaining the operation of the operation lever 31 that is horizontally rotated. FIG. 6 is a perspective view showing the operation lever 31. 7A and 7B are views showing the fork 32, where FIG. 7A is a plan view and FIG. 7B is a side view. 8A and 8B are views showing the cover 62, in which FIG. 8A is a plan view and FIG. 8B is a side view. FIG. 9 is a plan view showing the slide plate 63. 10A and 10B are enlarged views of the mode switching mechanism 61, in which FIG. 10A shows a state in which the slide plate 63 has moved to the right, FIG. 10B shows a state in which the slide plate 63 is in the neutral position, and FIG. Shows the state of moving to the left. 11A and 11B are diagrams for explaining the overstroke mode, in which FIG. 11A is a neutral state with respect to rotation, FIG. 11B is a state in which the spool 36 is at the spool end in the spool pushing operation, and FIG. Indicates the overstroke status. 12A and 12B are diagrams illustrating the overstroke mode, where FIG. 12A is a neutral state with respect to rotation, FIG. 12B is a state in which the spool 36 is at the spool end in the spool pulling operation, and FIG. Indicates the overstroke status. FIG. 13 is a plan view showing the operation lever 101 including the mode switching mechanism 115 in the prior art. 14A and 14B are diagrams for explaining the overstroke mode in the prior art. FIG. 14A shows a state where the spool 102 is at the spool end in the spool pushing operation, and FIG. 14B shows an overstroke state in the spool pushing operation. 15A and 15B are diagrams for explaining the overstroke mode in the prior art, where FIG. 15A shows a state in which the spool 102 is at the spool end in the spool pulling operation, and FIG. 15B shows an overstroke state in the spool pulling operation.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings as appropriate. In addition, this embodiment is only 1 aspect of this invention, and it cannot be overemphasized that an embodiment may be changed in the range which does not change the summary of this invention.

[Vehicle-mounted crane 10]

1 and 2 are a left side view and a rear view of the vehicle-mounted crane 10.

The vehicle-mounted crane 10 is mounted on a work vehicle and is driven by a hydraulic mechanism that uses the engine of the work vehicle as a drive source. In FIG. 1, the direction indicated by reference numeral 8 is the traveling direction of the work vehicle on which the vehicle-mounted crane 10 is mounted, and this direction is defined as the front-rear direction 8. A direction indicated by reference numeral 7 is defined as a vertical direction 7 (generally a vertical direction), and a direction orthogonal to the vertical direction 7 and the front-rear direction 8 is defined as a horizontal direction 9.

The vehicle-mounted crane 10 according to this embodiment includes a main beam 11, a jack 12, a swivel base 13, a swivel post 14, a boom 15, a hoisting cylinder 16, a winch 17, a wire rope 18, and a hook. 19 is mainly provided.

The vehicle-mounted crane 10 has a main beam 11 fixed on the frame of the work vehicle. A slide beam extending in the left-right direction 9 is disposed in the main beam 11 formed in a box shape having a rectangular cross section, and the jack 12 supported by the slide beam extends and contacts the ground, thereby ensuring the stability of the vehicle. The The swivel base 13 is provided on the main beam 11 and is rotatable around a rotation center axis along the vertical direction 7. The swivel post 14 is erected on the swivel base 13 and rotates together with the swivel base 13. The boom 15 is provided at the upper end of the turning post 14. The base end portion 15A of the boom 15 is connected to the turning post 14 via a undulation center pin, and the undulation operation is possible.

The boom 15 includes a base boom 21, an intermediate boom 22, and a top boom 23. The intermediate boom 22 and the top boom 23 are telescopically stored in the base boom 21. Thereby, the boom 15 is comprised so that expansion-contraction is possible. The hoisting cylinder 16 is for hoisting the boom 15. The boom 15 has a built-in telescopic cylinder, and the boom 15 expands and contracts when the telescopic cylinder expands and contracts. The winch 17 is provided inside the turning post 14. The winch 17 extends or retracts the wire rope 18. The wire rope 18 hangs around the tip 15B of the boom 15, and a hook 19 is provided at the tip. When the winch 17 is rotated in a predetermined direction, the wire rope 18 is wound around the winch 17 and the hook 19 is raised. When the winch 17 is rotated in the anti-predetermined direction, the wire rope 18 is unwound from the winch 17 and the hook 19 is lowered.

[Operation lever device 30]

3 is a front view showing the operation lever device 30, FIG. 4 is a perspective view showing the operation lever 31 in a stacked state in the operation lever device 30, and FIG. 5 is an operation lever that is rotated horizontally. It is a top view for demonstrating the operation | movement of 31. FIG.

The vehicle-mounted crane 10 is hydraulically driven by a hydraulic circuit and includes an operation lever device 30 for operating the hydraulic circuit. The operation lever device 30 is for operating expansion and contraction of the boom 15, raising and lowering of the boom 15, rotation of the winch 17, rotation of the swivel base 13, and expansion and contraction of the jack 12. The operation lever device 30 includes a boom telescopic operation lever 31A, a boom raising / lowering operation lever 31B, a winch operation lever 31C, a turning operation lever 31D, and jack operation levers 31E and 31F, and is collectively referred to as an operation lever 31. Sometimes.

As shown in FIG. 3, one operation lever 31 corresponding to each operation is provided on each of the left and right sides of the vehicle-mounted crane 10. A base end portion 56 (see FIG. 5) of the operation lever 31 is provided with a fork 32 (corresponding to a “base” described in claims), which will be described later (see FIG. 4). The fork 32 is rotatably provided on a rotation shaft 33 (corresponding to a “predetermined rotation axis” recited in the claims) extending in the vertical direction 7. A pair of forks 32 arranged on the left and right are connected by a rod 34 (see FIG. 5), and when one operating lever 31 is rotated, the corresponding other operating lever 31 is rotated in conjunction. As a result, the operator can operate from either the left or right side of the vehicle.

[Hydraulic control valve 35]

As shown in FIG. 3, the operating lever device 30 includes a hydraulic control valve 35 of a hydraulic circuit corresponding to each operating

lever

31A, 31B, 31C, 31D, 31E, 31F. As shown in FIG. 5, the hydraulic control valve 35 includes a spool 36 that extends in the left-right direction 9 and slides in the same direction. The end of each spool 36 is connected to a slide plate 63 (see FIG. 6 described later) supported by a fork 32 of each operation lever 31 via a connection pin 37. Therefore, when the operation lever 31 is turned by the operator, the fork 32 is turned around the turning shaft 33, and the spool 36 is linearly moved leftward or rightward. As a result, the hydraulic control valve 35 is switched.

[Operation lever 31]

6 is a perspective view showing the operation lever 31, FIG. 7 is a view showing the shape of the fork 32, FIG. 8 is a view showing the shape of the cover 62, and FIG. It is a figure which shows a shape.

As shown in FIG. 6, the operation lever 31 includes a fork 32, a handle 41, a cover 62 (corresponding to a “guide plate” described in claims), a slide plate 63, and a coil spring 64 (patent). Equivalent to the “elastic member” recited in the claims). In the following description of the operation lever 31, it is assumed that the operation lever 31 provided on the left side of the vehicle is in a neutral position (a state where the operation is not turned).

[Handle 41]

As shown in FIG. 6, the handle 41 is a round bar in the present embodiment, extends leftward from the base end portion 56, bends in the middle, and extends in a predetermined direction, for example, diagonally upward to the left. A handle 57 may be attached to the grip portion 55 of the handle 41 (the end opposite to the base end portion 56) as shown in FIG. The shape of the handle 57 is formed so that the operator can easily grip the grip portion 55 of the handle 41.

[Fork 32]

7, the fork 32 includes an upper plate 44, a lower plate 45, and a side plate 46, and has a substantially C-shaped cross section. The upper plate 44, the lower plate 45 and the side plate 46 are integrally formed. The upper plate 44 has a shape in which a central portion at the right end is notched in a trapezoidal shape on the left side. The lower plate 45 is positioned below the upper plate 44 with a space from the upper plate 44. The side plate 46 has a substantially rectangular shape as shown in FIG. 5B, and is spanned between an end edge 47 of the upper plate 44 and an end edge (not shown) of the lower plate 45.

The fork 32 includes a rotation shaft insertion hole 51, a handle insertion hole 53, and a slide hole 54 (corresponding to a “through hole” recited in the claims). The rotation shaft insertion hole 51 is a circular hole and penetrates the upper plate 44 and the lower plate 45 along the vertical direction 7. The rotation shaft 33 (see FIGS. 3 and 5) is inserted through the rotation shaft insertion hole 51. Thereby, the fork 32 can be rotated along a plane orthogonal to the rotation shaft 33 around the rotation shaft 33. The handle insertion hole 53 is a circular hole and penetrates the side plate 46 in the left-right direction 9. As shown in FIG. 6, the base end portion 56 of the handle 41 is fitted into the handle insertion hole 53 (see FIG. 7) from the left and welded. Thereby, the handle 41 is fixed to the fork 32. As shown in FIG. 7, the slide hole 54 has an elongated rectangular shape extending in the front-rear direction 8. The slide hole 54 penetrates the side plate 46 in the left-right direction 9. The slide hole 54 will be described in detail later.

[Mode switching mechanism 61]

As shown in FIG. 6, the operation lever 31 includes a mode switching mechanism 61. By this mode switching mechanism 61, the operation mode of the operation lever 31 is switched to either the normal stroke mode or the overstroke mode. The mode switching mechanism 61 includes a cover 62, a slide plate 63, and a coil spring 64.

The cover 62 is stretched between the side plate 46 of the fork 32 and the handle 41. As shown in FIGS. 6 and 8, the cover 62 is a mountain-shaped member formed by bending an elongated plate-shaped member at a right angle. The cover 62 includes a first plate portion 65 extending in the left-right direction 9 and a second plate portion 66 extending in the front-rear direction 8. As shown in FIG. 6, the right edge 67 of the first plate portion 65 is connected to the left surface 68 of the side plate 46 of the fork 32 (corresponding to “wall portion” and “seat surface” recited in the claims). Has been. As shown in FIG. 8, the rear end portion of the second plate portion 66 has a through hole 71 that penetrates in the left-right direction 9. As shown in FIG. 6, the base end portion 56 of the handle 41 is inserted into the through hole 71 of the cover 62. The base end portion 56 of the handle 41 and the through hole 71 are fixed by welding, for example. As shown in FIG. 8, the second plate portion 66 has a slide hole 72 (corresponding to a “through hole” described in claims) that penetrates in the left-right direction 9. The slide hole 72 has the same shape as the slide hole 54 (see FIG. 7) of the fork 32. The slide hole 72 is opposed to the slide hole 54 in the left-right direction, and is disposed at the same position in the up-down direction 7 and the front-rear direction 8 (see FIG. 10).

As shown in FIG. 9, the slide plate 63 is a substantially rectangular plate-shaped flat bar. The slide plate 63 has a rectangular through hole 73 (corresponding to an “opening” recited in the claims) penetrating in the vertical direction 7 (direction perpendicular to the paper surface). A projecting piece 75 (corresponding to an “engagement portion” described in claims) is formed on the right end surface 74A of the inner peripheral surface 74 of the through hole 73. The protruding piece 75 has a rectangular shape and protrudes to the left. A projecting piece 78 (corresponding to an “engagement portion” described in claims) is formed on the left end surface 74B of the inner peripheral surface 74 of the through hole 73. The projecting piece 78 has the same shape as the projecting piece 75, protrudes rightward from the left end surface 74 </ b> B, and faces the projecting piece 78. The dimensions of the projecting piece 75 and the projecting piece 78 in the front-rear direction 8 are the same, and are substantially the same as the inner diameter of a coil spring 64 described later. An engagement portion 81 is provided on the right end surface 80 of the slide plate 63. The engaging portion 81 protrudes rightward from the right end surface 80. The engaging portion 81 has a through hole 82 that penetrates in the vertical direction 7. As shown in FIG. 10, the slide plate 63 is described in the left-right direction 9 (described in claims) in the slide hole 54 (see FIG. 7) of the fork 32 and the slide hole 72 (see FIG. 8) of the cover 62. It is slidably inserted in the “sliding direction” (see FIG. 6).

As shown in FIG. 10, the coil spring 64 includes the left surface 68 of the side plate 46 of the fork 32 and the right surface 66A of the second plate portion 66 of the cover 62 (“side portion” and “sheet surface” recited in the claims). Between the left end surface 74B and the right end surface 74A of the through hole 73 (see FIG. 9) of the slide plate 63 in a compressed state by a predetermined initial compression amount. Is done. The right end portion of the coil spring 64 contacts at least one of the left surface 68 of the side plate 46 of the fork 32 and the right end surface 74A of the through hole 73 of the slide plate 63. Further, the left end portion of the coil spring 64 is in contact with at least one of the right surface 66A of the second plate portion 66 of the cover 62 and the left end surface 74B of the through hole 73 of the slide plate 63. With the coil spring 64 set, the projecting pieces 75 and 78 (see FIG. 9) formed on the inner peripheral surface 74 of the through hole 73 of the slide plate 63 are inserted inside the coil spring 64. Thereby, the movement of the coil spring 64 in the front-rear direction 8 is restricted.

[Operation of Mode Switching Mechanism 61]

10A and 10B are plan views showing the operation of the mode switching mechanism 61, where FIG. 10A shows a state where the slide plate 63 has moved to the right from the neutral position, and FIG. 10B shows a steady state where the slide plate 63 is located at the neutral position. (C) shows a state in which the slide plate 63 has moved to the left from the neutral position.

10B, when the slide plate 63 moves to the right with respect to the fork 32, the state shown in FIG. 10A is reached. 10A, compared with the state shown in FIG. 10B, the left end surface of the left surface 68 of the side plate 46 of the fork 32 and the through-hole 73 of the slide plate 63 (see FIG. 9). The interval with 74B is reduced. The right end of the coil spring 64 is in contact with the left surface 68 of the side plate 46, and the coil spring 64 is restricted from moving to the right, so that the coil spring 64 is further compressed from the initial compression amount. At this time, the distance between the through hole 82 of the engaging portion 81 and the side plate 46 of the fork 32 in the slide plate 63 is longer than that in the steady state shown in FIG. In the state shown in FIG. 10A, the urging force of the coil spring 64 acts on the slide plate 63 so that the slide plate 63 returns to the neutral position shown in FIG.

10B, when the slide plate 63 moves to the left with respect to the fork 32, the state shown in FIG. 10C is reached. In the state shown in FIG. 10C, compared to the state shown in FIG. 10B, the right surface 66A of the second plate portion 66 of the cover 62 and the through-hole 73 of the slide plate 63 (see FIG. 9). At the right end surface 74A. Since the left end of the coil spring 64 is in contact with the second plate portion 66 of the cover 62 and the coil spring 64 is restricted from moving leftward, the coil spring 64 is further compressed from the initial compression amount. At this time, the distance between the through hole 82 of the engaging portion 81 and the side plate 46 of the fork 32 in the slide plate 63 is shorter than that in the steady state shown in FIG. In the state shown in FIG. 10C, the urging force of the coil spring 64 acts on the slide plate 63 so that the slide plate 63 returns to the neutral position shown in FIG.

[Overstroke mode]

11 and 12 are diagrams for explaining the operation of the mode switching mechanism 61 in the overstroke mode.

FIG. 11 shows a state of the mode switching mechanism 61 when the handle 41 is turned from the neutral position in the direction of the arrow 87 by the operator.

FIG. 11A shows the mode switching mechanism 61 in a state where the handle 41 and the slide plate 63 are in the neutral position (see FIG. 10B). In this state, the engaging portion 81 of the slide plate 63 does not apply a force for moving the spool 36 to the spool 36, so that no drag force from the spool 36 is applied to the engaging portion 81. Therefore, the mode switching mechanism 61 is in a neutral state, that is, a state in which the slide plate 63 has not moved in the left-right direction 9 from the neutral position. In this state, the coil spring 64 is compressed by a predetermined initial compression amount. In this state, the work device (vehicle-mounted crane 10) does not operate.

When the handle 41 is rotated in the direction of the arrow 87 from the state shown in FIG. 11A, the fork 32 rotates in the direction of the arrow 87 about the rotation shaft 33 until the spool 36 reaches the spool end. Moving in the direction of the arrow 88, the mode switching mechanism 61 reaches the state shown in FIG.

Specifically, in the process from the state shown in FIG. 11A to the state shown in FIG. 11B, the engaging portion 81 of the slide plate 63 applies a force to the spool 36 in the direction of the arrow 88. . Therefore, a force in the direction opposite to the arrow 88 is applied to the engaging portion 81 as a drag force from the spool 36. However, the coil spring 64 of the mode switching mechanism 61 is not compressed even when a force necessary to move the spool 36 in the direction of the arrow 88 is applied. That is, the force required to further compress the coil spring 64 from the initial compression amount is greater than the force required to compress a spring (not shown) that biases the spool 36 to the neutral position in the hydraulic control valve 35. Therefore, the coil spring 64 is not compressed from the initial compression amount, and the slide plate 63 does not move relative to the fork 32. Therefore, the engaging portion 81 moves in the direction of the arrow 88, and the spool 36 moves linearly in the direction of the arrow 88.

The operation mode of the operation lever 31 from the state shown in FIG. 11 (A) to the state shown in FIG. 11 (B) is a normal stroke mode. In the normal stroke mode, the state of the hydraulic control valve 35 (see FIG. 5) that determines the operation direction (for example, the turning direction of the turntable 13) and the operation speed (for example, the turn speed of the turntable 13) of the work device is It is determined by the position of the spool 36 in the arrow direction 88. Therefore, the working device operates in a predetermined direction by the turning operation of the operation lever 31 from the state shown in FIG. 11A to the state shown in FIG. Further, the work device operates at a speed corresponding to the movement amount of the spool 36.

When the handle 41 is further rotated in the direction of the arrow 87 from the state shown in FIG. 11B, the spool 36 remains at the spool end (see FIG. 11B) and the rotation shaft 33 is centered. The fork 32 further rotates in the direction of the arrow 87, and the mode switching mechanism 61 reaches the state shown in FIG.

Specifically, in the state shown in FIG. 11 (B), the spool 36 has already reached the spool end and cannot move in the direction of the arrow 88. Therefore, in the process from the state shown in FIG. 11B to the state shown in FIG. 11C, the coil spring 64 is further compressed from the initial compression amount, and the slide plate 63 slides in the sliding direction 90. Therefore, the interval between the engaging portion 81 and the second plate portion 66 of the cover 62 is shortened. Thereby, the fork 32 further rotates from the position shown in FIG. 11B while the spool 36 is stopped at the spool end.

The operation mode of the operation lever 31 from the state shown in FIG. 11 (B) to the state shown in FIG. 11 (C) is an overstroke mode. In the overstroke mode, the opening of the engine throttle that determines the operating speed of the work device is determined by the rotational position of the fork 32. Therefore, the engine throttle is opened by the turning operation of the operation lever 31 from the state shown in FIG. 11B to the state shown in FIG. 11C, and the operating speed of the working device is set according to the opening of the engine throttle. Go up further.

FIG. 12 shows the state of the mode switching mechanism 61 when the handle 41 is turned from the neutral position in the direction of the arrow 86 by the operator. The state of the mode switching mechanism 61 shown in FIG. 12 (A) is the same as the state of the mode switching mechanism 61 shown in FIG. 11 (A).

When the handle 41 is rotated in the direction of the arrow 86 from the state shown in FIG. 12A, the fork 32 rotates in the direction of the arrow 86 around the rotation shaft 33, and the spool 36 reaches the spool end. Until the mode switching mechanism 61 reaches the state shown in FIG.

Specifically, in the process from the state shown in FIG. 12A to the state shown in FIG. 12B, the engaging portion 81 of the slide plate 63 applies a force to the spool 36 in the direction of the arrow 89. . Therefore, a force in the direction opposite to the arrow 89 is applied to the engaging portion 81 as a drag force from the spool 36. However, a coil spring 64 of the mode switching mechanism 61 is used that is not compressed even when a force necessary to move the spool 36 in the direction of the arrow 89 is applied. That is, the force required to further compress the coil spring 64 from the initial compression amount is greater than the force required to compress a spring (not shown) that biases the spool 36 to the neutral position in the hydraulic control valve 35. Therefore, the coil spring 64 is not compressed from the initial compression amount, and the slide plate 63 does not move relative to the fork 32. Therefore, the engaging portion moves in the direction of the arrow 89, and the spool 36 moves linearly in the direction of the arrow 89.

The operation mode of the operation lever 31 from the state shown in FIG. 12 (A) to the state shown in FIG. 12 (B) is the normal stroke mode.

When the handle 41 is further rotated in the direction of the arrow 86 from the state shown in FIG. 12B, the spool 36 remains at the spool end (see FIG. 12B) and the rotation shaft 33 is set as the center. The fork 32 further rotates in the direction of the arrow 86, and the mode switching mechanism 61 reaches the state shown in FIG.

Specifically, in the state shown in FIG. 12B, the spool 36 has already reached the spool end and cannot move in the direction of the arrow 89. Therefore, in the process from the state shown in FIG. 12B to the state shown in FIG. 12C, the coil spring 64 is further compressed from the initial compression amount, and the slide plate 63 slides in the sliding direction 91. Therefore, the interval between the engaging portion 81 and the second plate portion 66 of the cover 62 becomes long. Thereby, the fork 32 further rotates from the position shown in FIG. 12B while the spool 36 is stopped at the spool end.

The operation mode of the operation lever 31 shown in FIG. 12C from the state of the operation lever 31 shown in FIG. 12B is an overstroke mode.

[Operational effects of this embodiment]

As described above, as shown in FIG. 6, the structure in which the operation lever 31 exhibits the overstroke function is realized by only a part of the fork 32, the slide plate 63, the cover 62, and the coil spring 64. Moreover, the coil spring 64 does not require a special structure, and the slide plate 63 and the cover 62 are the same. Therefore, the manufacture of these parts does not require drawing, lathe, or other machining as in the prior art, and the number of parts of the operating lever 31 is reduced as compared with the prior art.

As shown in FIG. 10, when the slide plate 63 is in the neutral position shown in FIG. 10B, the coil spring 64 has the left surface 68 of the side plate 46 of the fork 32 and the right surface 66 </ b> A of the second plate portion 66 of the cover 62. Held between. The left surface 68 of the side plate 46 of the fork 32 is constituted by a part of the fork 32, and the right surface 66A of the second plate portion 66 of the cover 62 is constituted by a part of the cover 62. No parts are required. When the slide plate 63 is slid in the overstroke mode, the coil spring 64 is arranged between the left surface 68 of the side plate 46 of the fork 32 and the left end surface 74B of the through hole 73 of the slide plate 63, or through the through hole 73 of the slide plate 63. Is sandwiched between the right end surface 74A and the right surface 66A of the second plate portion 66 of the cover 62, exerts an elastic force, and attempts to return the slide plate 63 to the neutral position.

The left surface 68 of the side plate 46 of the fork 32 and the right surface 66A of the second plate portion 66 of the cover 62 are composed of simple members. Moreover, slide holes 54 and 72 are formed in the left surface 68 of the side plate 46 of the fork 32 and the right surface 66A of the second plate portion 66 of the cover 62, so that the slide plate 63 can slide in the left-right direction 9 (see FIG. 10). Retained. That is, the slide plate 63 is supported with a simple structure.

A coil spring 64 interposed between the fork 32 and the cover 62 is disposed in the through hole 73 (see FIG. 9) of the slide plate 63. Therefore, the fork 32, the slide plate 63, the cover 62, and the coil spring 64 are laid out in a compact manner. Moreover, this layout is very easy to implement.

The coil spring 64 and the slide plate 63 may be general-purpose products. In addition, since the coil spring 64 is supported by a pair of

protrusions

75 and 78 provided on the slide plate 63, the coil spring 64 is easily and reliably held at the neutral position, and the slide plate 63 is slid. Even if it exists, the coil spring 64 can be elastically deformed stably.

[Modification]

In the above-described embodiment, the cover 62 has one end fixed to the fork 32 and the other end fixed to the handle 41. However, the cover 62 may be fixed only to the handle 41 or may be fixed only to the fork 32. For example, the cover 62 is formed in a U-shape and both ends are fixed to the fork 32 or the handle 41, so that the cover 62 is fixed to only one of the fork 32 or the handle 41.

In the above-described embodiment, the coil spring 64 is used as the elastic body, but various elastic bodies such as rubber and a torsion spring may be used instead of the coil spring 64.

In addition to the projecting

pieces

75 and 78 of the slide plate 63, projecting pieces to be inserted into the coil spring 64 are also formed on the left surface 68 of the side plate 46 of the fork 32 and the right surface 66 </ b> A of the second plate portion 66 of the cover 62. It may be. As a result, the slide plate 63 is slid, so that one end of the coil spring 64 is supported by the projecting

pieces

75 and 78 even in a state where the end of the coil spring 64 is not supported by either one of the projecting

pieces

75 and 78 of the slide plate 63. Since the end portion of the coil spring 64 that is not provided is supported by the projecting piece of the fork 32 or the cover 62, the coil spring 64 can be stably elastically deformed.

The operation lever 31 according to the present invention may be used in a working device other than the vehicle-mounted crane 10.

33 ... Rotation axis (rotation axis)
32 ... Fork (base)
41 ... handle 36 ... spool (operation target)
9 ... Left-right direction (sliding direction)
63 ... Slide plate 62 ... Cover (guide plate, angle member)
64... Coil spring (elastic member)
31 ... Control lever 68 ... Left surface (wall, sheet surface)
66A ... right side (side, sheet side)
75, 78 ... Projection piece (engagement part)
72 ... slide hole (through hole)
54 ... Slide hole (through hole)
73 ... Through hole (opening)
74 ... Inner peripheral surface

Claims

A base that can rotate about a predetermined axis of rotation;
A handle provided on the base, for rotating the base around the rotation axis;
A slide plate supported by the base in a state in which the operation target is connected and is capable of reciprocating along a slide direction orthogonal to the rotation axis with respect to a predetermined neutral position;
A guide plate for guiding the reciprocating movement of the slide plate;
The slide plate is disposed between the base and the guide plate and engaged with the slide plate, and urges the slide plate to return to the neutral position when the slide plate slides from the neutral position. An operation lever provided with an elastic member.
A pair of seat surfaces facing the slide direction are formed on the base and the guide plate, and the elastic member is held on the pair of seat surfaces in a state where the slide plate is in the neutral position. ,
The slide plate has a pair of engaging portions facing along the slide direction,
One engaging portion engages with the elastic member instead of the seat surface of the guide plate when the slide plate slides to one side in the sliding direction, and the elastic member is placed between the seat surface of the base. Formed to be sandwiched between
The other engaging portion engages with the elastic member instead of the seat surface of the base when the slide plate slides to the other side in the sliding direction, and the elastic member is placed between the seat surface of the guide plate. The operation lever according to claim 1, wherein the operation lever is formed so as to be held between the two.
The seat surface of the base is composed of a wall portion orthogonal to the sliding direction, and the wall portion has a through-hole into which the slide plate is slidably fitted and restricts insertion of the elastic member. ,
The guide plate has a pair of side portions, and is formed of a mountain-shaped member erected between the base and the handle, and the sheet surface of the guide plate is disposed opposite to the wall portion. The operating lever according to claim 2, comprising a side portion, and the one side portion has a through hole into which the slide plate is slidably fitted and restricts insertion of the elastic member.
An opening penetrating in the direction along the rotation axis is provided at the center of the slide plate, and the pair of engaging portions are formed in a portion of the inner peripheral surface of the opening that is opposed along the slide direction. ,
The operation lever according to claim 2, wherein the elastic member is disposed in the opening.
The elastic member is a coil spring having a predetermined inner diameter,
The operation lever according to claim 4, wherein the slide member is a flat bar, the opening has a rectangular shape, and the pair of engaging portions are projecting pieces inserted into the coil spring.